The Upper Tisa Valley. Preparatory proposal for Ramsay

surrounding plain as an island in which faunas corresponding with 3 fauna-zones
distinct from one another, have survived still in these days.
The recent microclimatic and malacological investigations (Sólymos, 1997,
Sólymos-Nagy, 1997) suggest that the microclimate of the hill slopes has direct and
indirect effects on molluscs. Direct effects are linked with the temperature and the
relative humidity of the biotope. The interrelation between the air and the plants has an
indirect effect: closed and transitional vegetation can keep an increase in humidity,
which is favourable for molluscs. This interrelation is very important because plants as
generative surface generate the microclimate and this microclimate provides many
other living organisms, such as molluscs with proper conditions. It seems to us that
some different microclimatic mosaics and lithobiomes (Huggett, 1995) developed on
the slopes of Kaszony Hill, thus the different ecological habitat loving Mollusc species
(e.g. open or shade loving communities) can live close to each other.
According to the qurtermalacological data (Sümegi-Szabó, 1992) similar
mosaic-like habitat developed on these hill slopes during the Pleistocene when the
“cold stage” taxa and “warm stage” taxa (Willis et al. 1995) could survive some
different climatic changes in small approving environmental pockets (or oasies: Willis
et al. 1998) therefore there were highly mixed communities in both flora and fauna.
Thus these hillslopes were favourable places for temperate refugial populations, firstly
Carpathian and Middle European forest elements.
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Malakofaunistical evaluation of two floodplain forests
The Chilostoma banaticum species, according to our researches live on two
floodplain regions of the Szatmár-Bereg Plain. It was first discovered by Bába (1969)
in the Bagiszeg Forest belonging to a town of Vásárosnamény. Later it was also found
in Szabó-füzes Forest near Tiszabecs (Fintha et al, 1993).
In the course of the biological inventory we collected samples from 8-8
quadrats, and a great amount of material was collected with the bulk method. On the
two territories we found 26 species altogether which is more than 50% of the species
found on the Szatmár-Bereg Plain. The common species almost without exception, are
of SE-European, European and Carpathian expansion.
Most of the snails, living only near Bagiszeg, are species existing in European
closed forests. All of the species living only in Tiszabecs are wide-spread holarctic and
palearctic ones which favoure humid, watery biotops independetly from light intensity.
The spectacular difference comes from the water-supply of the biotops. The odd thing
is that we found twice as many entities in Bagiszeg as in Tiszabecs from the same
amount of quadrats (8-8). This diversity cames from the great density of entities of the
small-sized species, which is due to the luxuriant undergrouth and the thicker forest
floor meaning a more favourable biotop for them.
According to our research besides Chilostoma banaticum as the dominant
species - we can also find Bradybaena fruticum, Helix pomatia, Cepaea vindobonensis